This week, Lena Dunham revealed on Instagram that changing her diet has helped her feel her best while living with endometriosis. As she put it: "some foods were not allowing me to perform at Beyoncé level."

This isn't the first time Dunham has spoken out about living with this painful chronic condition, and she isn't the only one — it's estimated that the hormonal disorder affects up to 10 percent of all women in America.

Endometriosis gets its name from the tissue in your uterus. In women who have endometriosis, the endometrial tissue actually grows outside the uterus and can be found in other parts of the abdomen, like on the ovaries and fallopian tubes.

This extra tissue acts just like the normal tissue in the uterus, and builds up once a cycle. Unfortunately, when it’s time for a period, this tissue becomes very inflamed and swollen, because it’s got nowhere to go! This ends up causing a lot of pain, fertility issues and gut problems (like diarrhea and abdominal cramps), among other issues.

Endometriosis is a chronic condition and research into how to manage it is still ongoing. However, as Dunham experienced in her own life, nutrition can play a role in lessening the pain and other symptoms associated with the disorder.

As a health coach and nutritionist, here's what I recommend eating if you have endometriosis:

1. Wild-Caught Salmon

A 2015 study suggests that vitamin D could be helpful in lessening the invasion and proliferation of endometrial cells. One marker of inflammation known as IL-6 (interleukin-6) was also decreased with the help of vitamin D.

Salmon is one of the highest vitamin D-containing foods out there. I recommend including vitamin D-rich sources like salmon or other fatty fish several times per week to assist in achieving adequate vitamin D and all its benefits.

Purchasing wild-caught (versus farmed) salmon helps ensure the quality of the nutrients, and makes sure you’re not getting a genetically modified fish, or the antibiotics and other toxins commonly found in farmed fish.

2. Bell Peppers

Raw bell peppers are one of the best food sources of vitamin C. And research in rats suggests that the vitamin may be beneficial for those with endometriosis. In the 2013 study, researchers found a significant reduction in the volume and weight of endometrial cysts with the consumption of vitamin C.

Because bell peppers are on the Environmental Working Group’s “Dirty Dozen” list of produce that are highest in pesticides, I recommend buying organic.

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3. Berries and Red Grapes

Berries of all kinds, especially dark ones like blueberries, and dark red grapes are great sources of resveratrol. You might have heard of this substance before, because it provides some of the health benefits of red wine. While I wouldn’t recommend alcohol consumption when trying to balance hormones, foods like berries and red grapes that contain resveratrol may be a great addition to an endometriosis diet.

An animal study found that resveratrol could be beneficial in endometriosis because of its anti-inflammatory and anti-angiogenic effects. Regular consumption of red grapes and dark berries could be a positive measure toward managing endometriosis.

4. Flaxseeds

Flaxseeds are potentially an excellent food for endometriosis. They contain very high levels of anti-inflammatory omega-3 fatty acids, and omega-3 consumption could be helpful for endometriosis.

Emerging research suggests that inflammatory markers such as interleukins and prostaglandins are reduced with consumption of omega-3s. Additionally, omega-3s were shown to reduce the survival of endometrial tissue.

5. Spinach

Spinach is definitely a favorite food of mine when it comes to balancing hormones. It’s loaded with iron, folate, fiber and lots of other phytonutrients.

One such phytonutrient is alpha lipoic acid, and a 2015 study suggests the consumption of alpha lipoic acid (in addition to other anti-inflammatories) can help reduce the size of endometrial cysts and reduce inflammation.

The folate in spinach could also be helpful for endometriosis. Folate, along with other vitamins and minerals, is inversely related to the risk of endometriosis.

While dealing with endometriosis is no woman’s idea of a picnic, incorporating these five foods into your diet could be very beneficial when consumed regularly. Better yet, make a salad out of all five!